The present invention relates generally to phased array antenna technology. Phased array antenna techniques show promise of providing high system reliability, high beam agility, flexible power control, beam shaping and stabilization, multiple-target capability and many other features. The application of these highly desirable antenna qualities is dependent upon low cost array components or multiple use of components. The adaptation of these antennas for fleet use has been awaiting development of technology that would provide complex, reliable and efficient circuits of relatively small size. This technology is developing rapidly, but still is not cost-effective.
Traditionally, the phased array antenna consists of many individual radiating elements which are excited through a corporate feed system to form a beam which is then steered in many planes by means of a phase shifter at each element. If N.sub.a is the number of elements in the azimuth plane, and N.sub.e is the number of elements in the elevation plane, then the total number, N, of phase shifters required is EQU N = N.sub.e N.sub.a ( 1),
and if a pencil beam is required then N.sub.a = N.sub.e and EQU N = N.sub.e.sup.2 ( 2).
Since the phase shifter and its associated driver account for about one-half of the total array cost, it is evident that a reduction in the number of phase shifters is necessary for any significant cost reduction.